Proportioning-scale.



A. L. BELL.

PROPORTIONING SCALE.

APPLICATION FILED on. 13. 1915.

1,279,829. Patented Sept. 24,1918.

WITNESSES: IN I/EN 70/? ATTORNEXI ARTHUR L. BELL, OF VANCOUVER, BRITISH COLUMBIA, CANADA.

PROPORTIONING-SCALE.

Specification of Letters Patent.

Patented Sept. 24, 1918.

Application filed October 13, 1915. Serial No. 55,721.

. enlargement be exposed to the camera and photographed together, as this not only economizes the time of the photographer but the expense of the subsequent treatment. The calculation necessary in such classification may be simple, but when a large number of pictures are being dealt with, the time occupied is considerable, and with a proportionate scale, such as is the subject of this application, the work of sorting may be rapidly done by an assistant and the time of the photographer saved.

The invention is fully set forth in the followin g specification, reference being made to the drawings by which it is accompanied, in which;

Figure 1 is a plan of the device.

Fig. 2, a section on the line aa to a. larger scale, and

Fig. 3, a similar view on the line b?).

The device comprises a base bar 2 of suitable length from each end of which members 3 and 4: project to opposite sides of the bar. From a position approximately in the middle of the bar 2 lines 5 and 6 are scribed on the members 3 and 4, which lines are normal to the middle line of the base bar 2 and are graduated in any convenient unit representing the unit used in measuring the pictures.

Adjacent the line 5 is a parallel slot 7 and in this slot a member 8 is endwise movable with provision by which it may be secured in any desired position of adjustment.

This endwise adjustable member 8 is provided with a pivot pin 9 coinciding with or immediately adjacent the intersection of the line 5 with the middle line of a bar 10, one end of which bar is mounted on the pivot pin 9. The other end of the bar 10 extends across the line 6 on tho op 'msito end 4- of the base bar 2 and, each end of thebar 10,

Wheredt crosses the lines 5 and 6, is beveled from opposite sides to the middle line to facilitate" adjustment to either scale or the reading of a scale dimension therefrom.

Intermediate of its ends the bar 10 passes through a clamp 11 which is pivotally mounted at 12 to a member 13 which is slidably mounted to move lengthwise on the bar 2, preferably in a lengthwise slot 14:.

The bar 10 is graduated, as at 15, toward the pivotal connection on the end 3 of the bar 2 for reductions, and as at 16, toward the other end for enlargements, from a zero point 0, corresponding with the beveled edge 17 of the clamp 11 when the pivot 12 on which the clamp is mounted is in the midposition between the two graduated lines 5 and 6. These graduations indicate any desired unit of linear measurement corresponding to the position of the camera from the object board.

The bar 10 being slidable in the clamp member 11, when that clamp is released, and the member 13 to which 11 is pivoted being slidable on the bar,2, if the pivoted end 9 of the bar 10 is clamped to a dimension on the graduated line 5 corresponding to the size of the picture which is required to be reduced or enlarged, the clamp 11 may be moved endwiSe on the bars 2 and '10 to adjust the other end of the bar 10 to the dimension on the line 6 of the reduction or enlargement required, and 11 being clamped, the position of its beveled edge will indicate on the scale 15 or 16, as the case may be, the ratio of such reduction or enlargement, or the distance of the camera from the copy board on which the picture is displayed for photographing: or, conversely, the clamp 11 being moved to a graduation on 15 or 16 corresponding to the fractional reduction or enlargement required the end of 10 will indicate on the graduated line 6 the dimension of the picture when so reduced or enlarged.

With this device a number of pictures which are required to be reduced or'enlarged are measured by the operator and the pivoted end of the bar 10 is set to the dimension on the scale 5 corresponding to that of the picture. The clamp 11 is then released and is moved along the base bar 2 until the other end of the bar 10 indicates on the scale 6 the size to which that picture is required to be reduced or enlarged.

Each picture being marked wlth this camera position they maythen be sorted out that all pictures requiring the same POSI- tion of the camera may be placed on the object board for photographing at one time.

There are various other devices to which the device may be put which wills suggest themselves to any one occupied in photoengraving or the kindred arts.

Although the lines 5 and 6 normal to the middle line are shown as arcs and the slot 7 is concentric with the arc 5, these lines and the slot may be straight lines at right angles to the middle line, without deviating from the essential feature of the invention as the same result will be efi'ected and possibly with greater exactitude, but the manner shown is preferred asthe result is suiticiently accurate for the purpose required and the end of the bar 10 does not project so far over the end of 2 as it otherwise would.

Having now particularly described my invention, I hereby declare that what I c aim as new and desire tobe protected in by Letters Patent, is:

1. A proportioning scale, comprising in combination, a base having a line scribed at each end on opposite sides of and normal to a medial line, a bar extending across the normal end lines and mounted at one end on a pivot to be adjustable alongone end line, a clamp which is pivotally connected on the medial line to amember which is endwise movable along that line and graduations on the end lines and movable bar by i wise adjustable in the slot, a movable bar pivotally connected at one end to the adjustable member of the slot and extending across both end lines, a clamp which is pivotally connected on the medial line to a member which is endwise slidable along the medial line, said clamp being movable along said movable bar intermediate of the ends of the same, said movable bar being graduated from a zero point corresponding to an indicating line on the clamp when the pivot of the clamp is midway between the graduated end lines.

3. A proportioning scale, comprising in combination, a base bar having a member projecting from each end to opposite sides of the medial line of the base bar one end member having a slot normal to the medial line of the base bar, a member slidable adjustable in the slot of the end member, a movable bar pivotally connected to the adjustable member of the slot and extending over both end members of the base bar, a member slidable on said movable bar in termediate the ends ofthe same, said member being pivotally connected to another member which is endwise slidable on the base bar, each end member of the base bar being angularly graduated by lines radial t0 the pivot of the movable bar when that pivot is approximately midway between the end members, and means for securing the movable bar in the member which is pivotally mounted on the slidable member of the end member of the base bar.

4:. A proportioning scale, comprising the combination with an elongated thin flat bar having oppositely turned ends on which'arcs are scribed and graduated from zero points at their intersection with the middle line of the bar, a secondary bar one end of which is pivotally adjustable along one of the arcs and extending across the other arc, a member'slidable on said bar, which member is pivotally connected to a member slidable along the middle line of the first named bar, means for clamping the pivotally adjustable end of the last named bar, and means for clamping the same bar to the member in which it is endwise movable.

5. A proportioning scale, comprising the combination with a base bar having end members projecting to opposite sides, each of said end members having a graduated arc scribed on it from the middle line of the base bar, the center from which such arcs are struck being on the middle line, one of said end members having a slot immediately adjacent and concentric with its arc, and a movable bar extending across both arcs one end of which is pivotally adjustable in the slot, a clamp slidable on said movable bar intermediate of the ends of the same which clamp is pivotally mounted in a member endwise movable alongthe middle line of the base bar, said movable bar being graduated each way from a zero point corresponding to an indicating line on the clamp when the ends of the bar are on the zero points of the end line graduations.

6. proportioning scale comprising in combmation with a base bar, end extensions carried by said bar and extending to opposite sides of the bar, there bein one extension at each end of the bar, sai bar having a longitudinal slot, a slide cooperating with said bar and slot and adapted to be moved endwise of the bar, a clamp. pivoted to said slide, another bar endwise movable in said clamp, said end extensions each having a line scribed on the same normal to a medial line of the bar center, one of said end extensions having a slot paralleling the adjacent line, a pivot member slidable on said slotted end extension along said slot and to which the adjacent end of said second bar is pivoted, means for retaining said bar end pivot member in its different positions along the slot of said end extension, substantially as shown and described.

7. A. proportional scale comprising in combination a base having a line scribed at each end on opposite sides of and normal to a medial line, a bar extending across the normal end lines, a pivotadjustable along 1 one end line to Which one end of said bar is pivoted, a member freely endWise movable rigidly secured to said bar independently of the member to Which the claim is itself pivoted, and graduations on the end lines and the movable bar by which the dimensions of the similar triangles may be ascertained, the graduations on said movable bar being graduated both ways from a middle zero point to give the position of the camera for enlargements or reductions.

In testimony whereof I afix my signature ARTHUR L. BELL, 

